bug fixes, contains method, updated docs

README

@@ -2,8 +2,8 @@ JavaScript library to generate recurring dates.
 
 For example:
 
-Every 2 weeks on Monday, Wednesday, and Friday for 5 occurrences starting today
-Every month on the last Sunday until 03/30/10 starting on 02/10/09
+Every 2 weeks on Monday, Wednesday, and Friday starting today for 5 occurrences
+Every month on the last Sunday starting on 02/10/09 until 03/30/10
 
 This library will generate a list of dates for those patterns.
 
@@ -19,7 +19,7 @@ USAGE
 var r = new Recurrence(pattern);
 alert(r.describe());
 dates = r.generate();
-
+if (r.contains('03/28/10')) alert('in pattern!');
 
 API
 
@@ -52,6 +52,14 @@ Tries to describe the supplied pattern in English.
 
 -----
 
+Boolean contains (date)
+
+Determines whether "date" is in the recurrence pattern. This calls generate(), if it hasn't already been generated, otherwise, it will use the dates generated from the last time generate() was called. Returns true if "date" is in the pattern. "date" can be either a string or a Date object, but please make sure the time portion is all balls.
+
+Note that this only check if "date" is contained within the pattern's starting and ending points. Next version will support indefinite ending date and throwaway dates generation, instead of storing them all in an array.
+
+-----
+
 Date[] generate ([limit])
 
 Generate the dates based on supplied pattern. Returns array of Date objects. Optional argument limit puts an upper limit on how many dates to generate (for preview or to prevent some memory leak).

VERSION

@@ -0,0 +1 @@
+1.0

recurrence.js

@@ -23,7 +23,7 @@
 var Recurrence = Class.create({
   // takes a JSON object with pattern options
   initialize: function (pattern, date_format) {
-    if (typeof pattern != 'object') throw new TypeError('pattern must be a JSON object');
+    if (typeof pattern != 'object') throw new TypeError('pattern must be a JSON');
 
     if (!pattern.every || pattern.every.blank()) {
       throw new ReferenceError('Every magnitude must be specified');
@@ -33,6 +33,9 @@ var Recurrence = Class.create({
       throw new TypeError('Every magnitude must be a valide number');
     }
 
+    // stores generated dates based on recurrence pattern
+    this.dates = [];
+
     this.start = Date.parse(pattern.start);
     this.every = parseInt(pattern.every);
     this.unit = pattern.unit;
@@ -60,19 +63,33 @@ var Recurrence = Class.create({
       }
       t.push('on ' + d.join(', '));
     } else if (this.unit == 'm') {
-      t.push('on the ' + nthword[(this.nth < 0) ? nthword.length : this.nth] + ' ' + week[this.occurrence_of]);
+      t.push('on the ' + nthword[(this.nth < 0) ? nthword.length-1 : this.nth] + ' ' + week[this.occurrence_of]);
     }
 
+    t.push('starting on ' + this.start.toString(this.date_format));
+
     if (this.end_condition == 'until') {
       t.push('until ' + this.until.toString(this.date_format));
     } else if (this.end_condition == 'for') {
       t.push('for ' + this.rfor + ' occurrences');
     }
 
-    t.push('starting on ' + this.start.toString(this.date_format));
     return t.join(' ');
   },
 
+  // determine whether given date is in recurrence
+  contains: function (d) {
+    if (this.dates.length == 0) this.generate();
+
+    // can be string or date object already
+    d = Date.parse(d);
+
+    for (var i = 0; i < this.dates.length; i++) {
+      if (Date.equals(this.dates[i], d)) return true;
+    }
+    return false;
+  },
+
   // returns an array of dates base on input pattern
   generate: function (max) {
     if (!(this.rfor || this.until || max)) {
@@ -82,7 +99,7 @@ var Recurrence = Class.create({
     var end_condition_reached = function (occurrences, current_date) {
       if (max && occurrences.length >= max) return true;
       if (this.end_condition == 'for' && this.rfor && occurrences.length >= this.rfor) return true;
-      if (this.end_condition == 'until' && this.until && current_date >= this.until) return true;
+      if (this.end_condition == 'until' && this.until && current_date > this.until) return true;
       return false;
     }.bind(this);
 
@@ -104,10 +121,10 @@ var Recurrence = Class.create({
       while (!end_condition_reached(dates, curr)) {
         // scan through the checked days
         this.days.each(function (d) {
-          if (end_condition_reached(dates, curr)) return;
-
           if (curr.getDay() < d) curr.moveToDayOfWeek(d);
+
           if (curr <= this.start) return;
+          if (end_condition_reached(dates, curr)) return;
 
           dates.push(curr.clone());
         }.bind(this));
@@ -126,7 +143,6 @@ var Recurrence = Class.create({
           curr.moveToNthOccurrence(this.occurrence_of, this.nth);
         }
 
-        // FIXME: breaking at the wrong time for until end conditoin
         if (end_condition_reached(dates, curr)) break;
 
         if (curr > this.start) {
@@ -148,7 +164,9 @@ var Recurrence = Class.create({
         dates.push(curr.clone());
       }
     }
-
-    return dates;
+
+    // cache results
+    this.dates = dates;
+    return this.dates;
   }
 });